This invention concerns fuel injector installations for internal combustion engines. Fuel injectors are employed in modern internal combustion piston engines to deliver a charge of fuel by injection to each engine cylinder during each complete engine cycle.
Typically, such injectors have a generally cylindrical body, and are mounted at the top end to an auxiliary fuel delivery pipe branched off from a main fuel pipe. This arrangement is referred to as a "top feed" installation.
The injector is sometimes threaded into a seat in the auxiliary fuel pipe. U.S. Pat. No. 5,005,878 issued on Apr. 9, 1991, for a "Coupler Element" and U.S. Pat. No. 5,038,738 issued on Aug. 13, 1991, for a "Fuel Injection Device for Internal Combustion Engines" each describe an installation for the fuel injectors using a clip which engages the fuel injector and which has portions snapping over flanges on the auxiliary fuel pipe. In U.S. Pat. No. 4,823,754 issued on Apr. 25, 1989 for a "Retaining Apparatus for Fuel Injectors in Internal Combustion Engine" there is described a clip with inwardly extending flanges slidable in grooves formed on either side of the fuel rail.
The tendency for this design to malfunction under hot fuel conditions has led to the development of the so-called "bottom feed" (or side feed) injector installation, in which injector cavity seats are formed in the fuel rail which each receive an injector body, and fuel flows into a port on the side of the injector.
This arrangement has heretofore required the use of relatively complicated retainers involving the use of a bolt and washer with a clip. This increases the material costs and assembly time, and automated assembly is difficult.
The present invention seeks to provide a simplified retainer installation for bottom feed/side feed fuel injectors which minimizes the assembly labor required and is readily adapted to automated assembly.